Electrochemically characterizing the ac–dc–ac accelerated test method using embedded electrodes

Theoretical analysis of electrochemical noise measurement with single substrate electrode configuration and examination of the effect of reference electrodes

“…These platinum foil sections were then connected to the working electrode terminals of the measuring instrument, whilst a single electrical connection from the metallic substrate was made to the reference electrode terminal. All researchers reported good correlation between ENM data obtained in this way and ENM data obtained by conventional means[28][29][30][31][32][33]. It is important to note that whilst the authors expect a minimal impedance contribution from platinum electrodes on ENM data, and whilst the experimental data referenced here appears to support this, the effects of pseudo-reference electrode impedance on ENM data for platinum foil electrodes has not been discussed or investigated specifically to date.Mabbutt et.al investigated the influence of different LREs and pseudo-reference electrodes specifically for the SS and NOCS electrode configurations, although the motivation for doing so was due to concerns over the noise intrinsic to LREs contributing to the measured noise data, and not due to the influence of LRE impedance[5].…”

“…To date, researchers that have used the SS technique to assess corroding bare metals and coated metallic substrates have been able to empirically validate their results in the laboratory with other electrochemical techniques, lending credibility to the SS configuration [5,[12][13][14][15][28][29][30][31][32][33]. It may be a safe assumption that the impedance of well-maintained LREs is negligible relative to a protective high impedance coating [14,15].…”

“…When presenting noise resistance data, use of the SS technique should be made clear, and the impedance of the LREs used should also be reported and compared with the noise resistance (Rn) values obtained.Alternatively, inert metallic electrodes such as platinum foil can be used as pseudoreference electrodes instead of LREs to acquire ENM data using the SS technique. Several researchers have demonstrated this as a viable method in the literature through the use of platinum foil electrodes embedded in organic coatings over metallic substrates[28][29][30][31][32][33]. In each instance, the researchers positioned a platinum foil electrode between the organic coating primer and topcoat, electrically isolating the foil from the metallic substrate and the external environment.…”

Electrochemical Evaluation Technologies of Organic Coatings

“…In addition, some in-situ test electrode techniques, such as microelectrodes or multiple electrodes, have been used for the application of EN in coating evaluation in the field or under some specific conditions. Bierwagen et al [33] have used the microelectrodes to study EN measurement of the coatings in a cyclic salt fog test chamber. Simpson et al [34] made a thin sheet of gold by electron-beam-deposition, which was deposited on the painted steel and served as the microelectrode.…”

Frontiers and Challenges in Electrochemical Corrosion Monitoring; Surface and Downhole Applications

“…Bierwagen et al [ 78 ] reported electrochemically ac–dc–ac accelerated test method using embedded electrodes in corrosion sensing for aircraft and vehicular structures. EN measurement and EIS methods were applied to monitor the changes in organic coatings.…”